1. Field of the Invention
The present invention relates generally to plumbing and other fittings in fluid lines or pipes in stationary structures, and more specifically to a cleanout fitting for installing in an evaporator drain line in an air conditioner system in a residence, office building, or other stationary structure. The present fitting allows water or air under high pressure to be forced through the line downstream of the evaporator pan without flowing into the pan, and also allows the line to the pan to be cleaned out with a plumber's cleanout tool or "snake" by means of a selectable valve.
2. Description of the Related Art
All air conditioning systems provide the same final result for air being processed or conditioned thereby, with the air being chilled as a result of contact with the very cold coils of the evaporator unit. In nearly every case, the evaporator coils are at a temperature very close to freezing, in order to impart the maximum cooling effect to the air. This results in much of the moisture which is being carried by the air, condensing out as the air is chilled. Accordingly, nearly all air conditioning evaporator units are provided with a drain pan and a drain line for draining condensed water from the area of the evaporator.
A problem occurs when the drain line becomes partially or completely blocked by dirt, dust, etc., over some period of time. Condensed water will then back up in the evaporator pan, and spill over into adjacent areas. Such evaporator drain line blockages must be taken care of quickly, in order to avoid water damage to the surrounding areas.
Yet, most such evaporator drain lines include a right angle fitting somewhere between the outlet end and the connection at the evaporator pan or air handler plenum. Moreover, such lines are generally formed of PVC plastic pipe with connections being cemented together to form a permanent installation. This requires the pipe to be cut apart in order to run a plumber's snake or other cleanout tool through the pipe, thus resulting in a relatively labor intensive and time consuming job. The alternative of flushing or blowing the blockage from the line cannot generally be used, as the line can generally only be easily accessed from its outlet end, thus resulting in blowing the blockage back into the evaporator pan and creating an unacceptable flow of water into the already flooded pan, if water is used. Moreover, such blowout and flushing methods often do not completely clean out a blocked area, but only remove a part of the blockage, with the relatively narrow cleared area being prone to further blockage in the immediate future.
Accordingly, a need will be seen for a cleanout fitting for an air conditioner evaporator drain, to allow the drain line to be accessed completely for thorough cleaning. An evaporator drain line equipped with the present fitting, does not need to be cut for cleanout purposes. Moreover, the present fitting with its selector valve enables all of the line downstream of the valve to be flushed or blown out with high pressure water or air, as desired. Opening the valve allows a cleanout tool or snake to be passed through that portion of the line all the way into the evaporator pan, in order to physically remove any blockage or obstruction therein.
A discussion of the related art of which the present inventor is aware, and its differences and distinctions from the present invention, is provided below.
U.S. Pat. No. 1,274,103 issued on Jul. 30, 1918 to Frank Story, titled "Device For Cleaning Pipes," describes a cleanout fitting comprising a rotary valve with a hollow shaft for blowing steam under high pressure through the valve and the attached pipes. The valve is installed in line in the pipe, with no T fitting provided for drainage. No removable cap is provided at one end of the line for the insertion of a cleanout tool through the pipe, whereas the present fitting includes such a removable cap at one end of the fitting to allow a cleanout tool to be inserted essentially straight through the fitting and pipe upstream of the fitting. Even if the pipe sections were disconnected, the male ends would not provide for the attachment of a male garden hose coupling, as provided by the present fitting.
U.S. Pat. No. 1,655,796 issued on Jan. 10, 1928 to Robert N. Murphy, titled "Plumbing Fitting," describes a fitting installed in the stem of a T in a plumbing line. The device permits the line to be flushed, but only in one direction at a time, depending upon the orientation of the valve of the fitting. In contrast, the valve of the present fitting may be opened completely, to allow flow in either direction and the passage of a cleanout tool straight therethrough. The Murphy valve fitting must be removed for normal flow through the pipe due to the one way nature of the valve and consequent blockage of flow through the pipe, whereas the present fitting remains in place at all times and provides for normal use of the drain.
U.S. Pat. No. 4,203,460 issued on May 20, 1980 to Werner K. Priese, titled "Ball Valve With Compound Closure Movement," describes a tapered seat valve for use in the food industry, for relatively high pressure flow. The Priese valve may be lifted slightly from its seat to relieve pressure on the seat, for easier turning of the valve. The Priese valve is not a T fitting, but includes a cleanout passage to the interior of the valve body. However, the relationship of the cleanout plug and passage and the valve, results in any flow introduced through the cleanout passage flowing in both directions through the line to either side of the valve, or no flow to either side. In contrast, the present fitting provides for flow in one direction when the valve is closed, and another when the valve is open. Also, Priese does not provide any means for attaching a conventional hose to his fitting.
U.S. Pat. No. 4,553,566 issued on Nov. 19, 1985 to John A. Barclay et al., titled "Rotary Multiposition Valve," describes a valve having multiple inlets and outlets, with rotation of the valve resulting in flow through a predetermined pair of the inlet and outlet lines. All of the lines are radially disposed, with no axial flow being possible completely through the Barclay et al. valve, unlike the present fitting. The Barclay et al. valve does not have a T configuration, and no fitting or means for attaching a conventional male connector from a garden hose is provided by Barclay et al. for his valve, whereas the present generally T shaped fitting includes such hose attachment means at one end of the crossmember portion of the T.
U.S. Pat. No. 4,998,412 issued on Mar. 12, 1991 to Joel Bell, titled "Blockage Alert And Purge System," describes a system for cleaning out air conditioner evaporator drain lines, including a T fitting installed in the line. However, the crossmember of the T is in continuous communication with the drain line, and as a result is inaccessible in a straight line, whereas the present fitting allows access for mechanical cleanout through one end of the T crossmember. Bell provides access to the line interior through the stem of the T, but thus requires high pressure fluid (air) to be blow through the line, as it is not possible to pass a mechanical cleanout tool past the ninety degree bends in the fitting. Moreover, Bell does not provide for connection to a conventional garden hose for economical flushing of the system, as provided by the present device.
U.S. Pat. No. 5,085,244 issued on Feb. 4, 1992 to Douglas H. Funk, titled "Assembly For Cleaning A Drain Conduit," describes a device having a T fitting located to each side of a generally centrally disposed valve. As the cleanout fittings are disposed at right angles to the line, a mechanical cleanout tool cannot be readily passed through the fittings to be run through the pipe, as provided by the present invention. Funk utilizes a vacuum to draw any blockage from the downstream side of the assembly, but utilizes high pressure air to blow back through the upstream side. The oftentimes only partial effectiveness of such blowout technique has been noted further above, and moreover, tends to blow the foreign matter far into the evaporator drain pan or plenum where it may flow back to the drain again in the near future.
U.S. Pat. No. 5,722,458 issued on Mar. 3, 1998 to Andrew M. Potter, titled "Valve For Clearing Air Conditioning Drain Lines," describes an in-line fitting providing for flow through the valve, or cutting off either side of the line from the valve as desired. Pressure or vacuum may be introduced into the top of the valve to attempt to remove a blockage in either direction, depending upon the orientation of the valve. The arrangement is more closely related to the assembly of the '103 U.S. patent to Story, discussed further above, than to the present invention. The configuration of the Potter valve does not permit a mechanical cleanout tool to be run straight through the line, as provided by the present fitting, nor can the Potter valve be economically flushed using a garden hose, as provided by the present fitting.
Canadian Patent Publication No. 482,593 issued on Apr. 22, 1952 to Archibald N. MacArthur, titled "Drain Pipe Blow-Out Plug," describes another assembly more closely related to the device of the Story '103 U.S. patent discussed further above, than to the present invention. The MacArthur assembly also provides a hollow valve stem, through which a fluid under pressure is introduced to the line to either side of the valve, depending on the orientation of the valve. The only access is through the hollow valve stem, with the stem oriented as the stem of a T in the line. Thus, no mechanical means may be readily used to pass straight through the crossmember of the T, as provided by the present fitting. Also, any fluid under pressure toward the upstream end of the assembly creates a backflow, flushing contaminants back to the drain pan where they will likely clog the drain again in short order; this problem is noted in other devices discussed further above as well.
Finally, British Patent Publication No. 2,212,597 published on Jul. 26, 1989 to Anthony T. Kirby-Suttle, titled "Control Valve For Fluid Flow," describes a spherical valve with two rotational axes. This allows the valve to align with one or the other openings through the valve body sides, normally used for rotating the valve. This allows a fluid to be passed into the valve to neutralize the effects of chemicals in the line. No T fitting is provided, nor is any means provided for the insertion of a mechanical cleanout tool straight through the valve, as provided by the present fitting.
None of the above inventions and patents, either singly or in combination, is seen to describe the instant invention as claimed.